Electromagnetic switch



June 1953 'r. J. WILSON ELECTROMAGNETIC SWITCH INSULATION Filed Jan. 5,1950 INSULATION THEODORE J. WILSON Oftorneg Patented June 16, 1953ELECTROMAGNETIC SWITCH Theodore J. Wilson, Minneapolis, Minn., assignorto Minneapolis-Honeywell Regulator Company, Minneapolis, Minn., acorporation of Delaware Application January 3, 1950, Serial No. 136,458

10 Claims.

This invention relates to electromagnetic switching devices and moreparticularly to the type known as vibrators. The prime object of thisinvention is to provide an improved vibrator design which is compact andrugged in construction-and reliable in operation.

It is further an object of this invention to provide a simplifiedvibrator design which is easy to assemble and maintain, and capable ofcarrying substantial currents and withstanding rough usage.

Another object of this invention is to provide an improved contactstructure for a device of this type which is simple to construct andassemble and maintain in adjustment.

Other objects and advantages reside in the details of construction whichwill become apparent upon reference to the accompanying specification,claims and drawing. For a better understanding of these objects,however, and the specific objects obtained by the present invention,reference should be had to the accompanying drawings, wherein:

Figure '1 is a plan view of the vibrator disclosing the subjectinvention,

Figure 2 is a side elevation view of the subject vibrator,

Figure 3 is an end elevation view of Figure 2 (in section) of thesubject vibrator disclosing the relationship of parts,

Figure 4 is .a schematic view of the vibrator to disclose relationshipof parts, and

Figure 5 is a sectional view of the vibrating reed with the electricalconnections thereto.

Figure 1 of the drawings shows a polarized electromagnetic vibratorembodying the principles of the present invention in which an armatureHi is mounted to move or vibrate under the influence of a plurality ofunidirectional magnetic fields created by a pair of permanent magnets IIand a pulsating or alternating field imposed on one end of the armaturell) adjacent the magnets I l, the latter or pulsating field beingcreated by an electrical winding 12 energized from an alternatingcurrent source of power.

The improved vibrator design of the subject invention is characterizedby its simple yet rugged construction, the component parts of which arecarried by a frame member I3 generally rectangular in form .and having alongitudinally extending slot I 4 therein of varying cross-section.Frame member [.3 is made of a suitable non-magnetic material which canbe either metallic or non-metallic. However, to provide a frame membercapable of withstanding Wear and abuse, it has been found satisfactoryto use a metal such as brass or aluminum. Slot M in frame member I3 issuitably formed, such as by machining or molding to provide the varyingdimensions or cross-sections therein. One extremity of slot I4 issubstantially reduced in width, as at It, and is designed to fit oraccommodate a root or shank 20 of armature 10 for the purpose ofsecurely attaching the armature to the frame and permitting pivotalmovement of the same. The root or shank 20 has an aperture therein (notshown) through which the armature is secured to the frame by means of abushing 2| inserted in an aperture 22 in the side of frame member l3,the bushing being clamped against the root or shank by means of a screw23 threaded into the frame member. Screw 23 is designed to fit into theframe member and secure the bushing in such a manner that it is recessedfrom the surface of the frame member to eliminate any projecting part.

Armature I0 is generally reed-like in form being made of a flexible andnon-magnetic material having a uniform cross-section except for theshank 20 and a notched end portion 24. Within the notches 24 in the endof reed or armature I0 is positioned a pair of plates of ma neticmaterial 25 to form a magnetic end for an otherwise non-magneticarmature. The plates 25 are attached to the reed or armature ID by anysuitable means such as rivets, and the plates are of such thickness thatin assembled relationship this end of the reed has substantially thesame cross section as the remaining portion of "the reed with theexception of the shank. These magnetic plates 25 on the end of reed I0are positioned between pole extremities 21, 28 of a pair of permanentmagnets H which provide the unidirectional magnetic fields for thevibrator. The magnets H are generally U-shaped in form as seen in Figure4 and are fitted into transversely extending slots in the end of theframe member opposite the mounting of the reed, the slots connectingwith the longitudinally extending slot I 4 such that the poleextremities 21, .28 terminate in the longitudinally extending slot andare positioned in near abutting relationship. Magnets l l are further sopositioned in this end of the frame member that the opposite or unlikepolarity ends of the magnets are .positioned adjacent one another todefine a pair of air gaps 32, 33 through which the magnetic portion ofthe reed, that is the plates 25, extend. The air gaps 32, 33 so amasosmature carrying the magnetic plates 25. Winding 12 is so shaped that itfits within the opening 35 so formed and lies between the bifurcatedportions of the permanent magnets II and the pole extremities 21, 28.Mounted on spool 3'1 through notches 40 therein are a pair of lead wireholders 4| to which holders the ends of the coil l2 are extended. Anexternal source of power, not shown, is connected to the coil throughsuitable leads shown at 43 which connect to the turns of the winding atthe extremities thereof mounted on' the holders 4|. If desired the inleads may be brought out from the Vibrator frame through a suitableaperture 44 therein such that the external connections to the in leadsmay be made from below the base of the frame. An insulating strip 46, asis shown in Figures 1, 2 and 3, is disposed above the coil and frame toinsulate the connections from the cover element 50 enclosing thisportion of the frame I3. The cover is connected to the end of thevibrator frame [3 by means of screws such as are shown at 52. As wasnoted above, Winding i2 is adapted to be energized from an A. C. sourceof power such that the extremities of the magnetic plate 25 on armatureit have imposed thereon magnetic polarities which alternate with thealternation or variation in current flow through the winding. Theconsequent attraction and repulsion between the poles formed in themagnetic plates and the poles of the permanent magnet cause vibration ofthe armature or reed ill in a well known manner.

Armature reed I0, as it vibrates under the influence or interaction ofthe magnetic fields, operates a contact structure, the movable portionof which is carried by reed or armature I0 within the longitudinallyextending slot I4 of frame l3. This movable portion of the contactstructure includes a pair of flexible contact blades 6| with contactmembers 62 mounted thereon, as by riveting or soldering, both the bladesand the contact members being made of an electrically conductivematerial. Blades 6| are attached to reed or armature H) bya plurality ofrivets 63 and are insulated from the reed or armature Ill, the rivets 63and one another by strips of insulation 65 and insulatin bushings 65, ascan be seen in Figure 4. Rivets G3 perform the function of holding theinsulating materials in position and rigidly securing one extremity ofthe blades 6| to the reed ID with the free extremity of the blades whichcarry the contacts 62 disposed substantially parallel to the reed. Freeextremities of blades 6| are held in a slightly biased or flexedrelationship by means of a blade catch 65 of insulating material mountedon blade or armature H]. The blade catch 65 is grooved or notched as at66 to receive the ends of the contact blades 6| during assembly and flexthe blades to a slightly biased condition in a manner Well known in theart of vibrators. The grooves 56 are suf- 4 ficiently large such thatmovement of the end of the blades therein permits suitable flexing ofthe blades upon contact with the stationary portion of the contactstructure later to be described. To accommodate such movement of theblades BI and the contacts 62 thereon, an aperture 10 is provided inreed or armature I!) such that the portion of the contact 62 adjacentthe reed will not contact the reed proper upon flexing of the contactblade. Aperture 10 permits such clearance for both contact structures62.

The movable portion of the contact structure at the contact 62 isdesigned to engage stationary portion of the contact structure which ismounted on frame l3, this stationary portion including contact blocks 12slidably positioned in transversely extending slots I3 in frame member[3 which slots communicate with the longitudinal slot M of the framemember. Each of the contact blocks 72 are made of a suitableelectrically conductive material and have an aperture 14 therein whichis slotted as at 15, the aperture being tapped and designed to receive athreaded contact pin 16 which is fitted to the contact block and extendsinto proximity With one of the movable contacts 62 of the flexibleblades 6| of the movable contact structure. The contact pins 16 aredesigned to be adjustably positioned within the blocks 12 to fix oradjust the spacing between the movable and stationary portions of thecontact structure. The blocks 12, one of which is positioned on eitherside of the movable contact structure, are insulated from the framemember 13 by means of an insulating member 11, also movable Within theslot 13.

The contact blocks 12, insulating members 11 and the contact pins 16after being positioned Within frame I3 and relative to one another arerigidly held in position in frame member I3 in the slots 13 by means ofL-shaped clamping members positioned on the frame l3 by means of pins 8|which extend through a receiving aperture'82 in said member. Anadjustable locking type screw member 83 extending through an aperture(not shown) in clamping member 80 and threading into the frame member I3exerts a downward force on clamping member such that the extremity incontact with the insulating member on contact block 12 holds the blockin a flxed and rigid relationship with the frame member. In addition,the clamping member 80 further exerts a force on the portions of thecontact blocks [2 surrounding the contact pin 16, and. by virtue of theslot 15 therein, is able to clamp the pin 76 in a rigid relationshipWith respect to the block after adjustment has been made to the same.

Electrical connections to the contact block and hence the pins it aremade by attaching leads to a contact block (not shown) by suitablemeans, such as soldering. Such leads, as are shown on 85, can be broughtout through suitable apertures in the end of the frame member and can beconnected in a circuit as desired. Similar connections, as shown at 86,are made to the ends of the flexible contact carrying blade members 6!and such connections mat also be brought out through the frame member toone end of the frame member. The contact structure as shown provides forindependent circuits through the individual contact carrying blades andstationary contact members formed by the contact pins and contactblocks.

conventional vibratingdevices. Energization .of

the winding 12 sets up the pair .of poles ,at the extremities of themagnetic :plates .25 attached :to the reed or armature 10. These. polesalternate with the variation or alternation in current supplied towinding [2 and react with the unidirectional .fields or poles set .up bythe magnets .11 to beattracted by one pair and repulsed by another asthe polarity of the reed or-armature changes. In the present arrangement.of :permanent magnets, an increased magnetic attraction betweenarmature and magnets is attained to provide for greater force-ofvibration and hence increase the capacity from the vibrator. Thecontact elements mounted -onthe reed and frame members willalternatelyengage and disengage as the armature or reed is vibrated tocomplete or break the circuit through the respective contact carryingmembers -and stationary contacts. With the present construction asubstantially increased-current carrying capacity for the vibrator isobtained and an arrangement is provided by which accurate adjustment maybe-made to the contact structure which will be maintained throughout thenormal operation of the device despite continued usage. Further, if itshould become necessary to adjust the contact structure; such adjustmentcan be made with ease.

In consideringthis invention-it should be kept in mind that the presentdisclosure is intended to be illustrative only and the scope of theinvention is to be determined only by the appended claims.

I claim as my invention:

1. In a vibratonanon-magnetic frame member having a pair of slots at oneend thereof, a pair of U-shaped permanent magnets mounted in said pairof slots in one end of said frame member and disposed with oppositepolarity extremities of said magnets in near abutting relationship todefine a pair of air gaps therebetween, a non-magnetic vibrating reedmember mounted at one extremity in the other end of said frame memberanddisposed with its free extremity in said air gaps, a pair of plates ofmagnetic material mounted on said free end of said flexible reed anddisposed adjacent the extremities of said permanent magnets, a coilencircling said free end of said reed and said plates of said magneticmaterial, said coil being positioned in anaperture in said frame memberand between the "extremi ties of said magnets and being adapted to beenergized with an alternating source of power to magnetize said plateswith alternating polarities such that said reed is attracted to theextremities of said magnets to cause vibration of said reed, and contactmeans mounted on said reed and insulated therefrom, said contact meanscooperating with'stationary contacts adj ustably mounted within saidframe and insulated therefrom, the vibration of said reed uponenergization of said coil causing alternating engagement of said contactmeans and said stationary contacts.

2. In a vibrator, a non-magnetic frame member, a pair of U-shapedpermanent magnets mounted in one end of said frame member 'and disposedwith opposite polarity extremities near abutting relationship to defineapair of :air .igaps therebetween, ,a anon-magnetic reed zmemb er, saidreed having an increased dimension at one extremity which fits into .aslot in said frame member removed from said permanent magnets, :meansincluding :a screw means for rigidly mounting said 'reedwithin saidslot, said freeextremity of said reed having notches :therein and beingdisposed in said gap between said magnets, a pair of plates of magneticmaterial positioned in said notches in said reed andattached thereto:being disposed to move with said reed within said air .gaps, a coilencirclingsaid free end ofsaidreed and said plates of magnetic material,said coil being positioned in an aperture in said frame member andbetween .the extremities of said'magnetland adapted to be energized withan alternating source of powerwhereby said plates are magnetized withalternating polarities such that said reed :is attracted to theextremities of said magnets to cause vibration .of said reed, andcontact means mounted on said reed and insulated therefrom, said-contactmeans cooperating with stationary contacts adjustably mounted withinsaid frame and insulated therefrom, the vibration of said reed uponenergization of said coil causing alternating engagement of said contactmeans and said stationary contacts.

3. In a vibrator, a non-magnetic unitary frame member having alongitudinal slot and a pair of transversely extending slots therein, apair of -U'-shaped permanent magnets mounted in said transverselyextending slots in one end of said frame member and disposed withopposite polarity extremities in near abutting relationship to define apair of air gaps therebetween, a flexible reed positioned in saidlongitudinal slot and secured at one extremity to said frame memberhaving a locus of pivot remote from said magnets with the free extremityof said reed-disposed within said air gaps, mag-netic means mounted onsaid extremity of said reed within said air gaps, an energizing windingpositioned with-in said'frame and between said magnets encircling saidmagnetic means and adapted to be energized from an alternating sourceofpower whereby said magnetic means is magnetized and attracted betweenthe extremities of said magnets to cause vibration of said reed, andcontact means mounted on said reed and insulated therefrom, said contactmeans cooperating with stationary contacts adjustably mounted withinsaid frame and insulated therefrom, the vibration of said reed uponenergization of said winding causing alternating engagement of saidcontact-means in said stationary contacts.

4. In a vibrator, a non-magnetic frame member, a pair of U-shapedpermanent magnets mounted in one end of said frame member and disposedwith opposite polarity extremities in near abutting relationship todefine a pair of air gaps therebetween, a non-magnetic reed member, saidreed having an increased dimension at one extremity which fits into aslot in said frame member removed from said permanent magnets, meansincluding a screw means for rigidly mounting said reed within said slot,said free extremity of said reed having notches therein and beingdisposed in said gap between said magnets, a pair of plates of magneticmaterial positioned in said notches in said reed and attached theretobeing disposed to move with said reed within said air gaps, a coilencircling said free end of said reed and sai plates of magneticmaterial, said coil being positioned in an aperture in said frame memberand between the extremities of said magnet and adapted to be energizedwith an alternating source of power whereby said plates are magnetizedwith alternating polarities such that said reed is attracted to theextremities of said magnets to cause vibration of said reed, and contactmeans including a first contact member attached to said reed and asecond contact member attached to said frame, said contact means beingadapted to be operated upon vibration of said reed.

5. In a vibrator, a non-magnetic frame member having a longitudinallyextending slot therein, a pair of U-shaped permanent magnet memberspositioned in transversely extending slots in one end of said framemember and extending into said longitudinally extending slot positionedwith the extremities of said'magnet in near abutting relationship, aflexible reed of non-magnetic material positioned in said longitudinallyextending slot and rigidly secured to said frame member at the oppositeextremity from said magnets, said reed at its free end being positionedbetween the ends of said permanent magnet, magnetic means mounted onsaid reed between said magnets, a coil encircling said free end of saidreed and said magnetic means and positioned within an aperture in saidframe between the extremities in said magnet, said coil being adapted tobe energized from a source of alternating current to magnetize saidmagnetic means with opposite polarities such that said reed is attractedbetween the extremities of said magnets to cause vibration of said reed,and contact means including a first contact member attached to said reedand a second contact member attached to said frame, said contact meansbeing adapted to be operated upon vibration of said reed.

6. In a vibrator, a non-magnetic frame member having a longitudinallyextending slot therein, a pair of U-shaped permanent magnet memberspositioned in transversely extending slots in one end of said framemember and extending into said longitudinally extending slot with theextremities of said magnets in near abutting relationship, a flexiblereed of non-magnetic material positioned in said longitudinallyextending slot and rigidly secured to said frame member at the oppositeextremity from said magnets, said reed at its free end being positionedbetween the ends of said permanent magnet, magnetic means mounted onsaid reed between said magnets, a coil encircling said free end of saidreed and said magnetic means and positioned within an aperture in saidframe between the extremities in said magnet, said coil being adapted tobe ener- I gized from a source of alternating current to magnetize saidmagnetic means with opposite polarities such that said reed is attractedbetween the extremities of said magnets to cause vibration of said reed,a pair of flexible contact carrying members mounted on and insulatedfrom said reed, and stationary contact members mounted on said framemember, said stationary contact members including mounting blocksslidably positioned in a second pair of transversely extending slots insaid frame member with contacts adjustably positioned therein.

'7. In a vibrator, a non-magnetic frame member having a longitudinallyextending slot therein, a pair of U-shaped permanent magnet memberspositioned in transversely extending slots in one end of said framemember and extending into said longitudinally extending slot with theextremities of said magnet in near abutting relationship, a flexiblereed of non-magnetic material positioned in said longitudinallyextending slot and rigidly secured to said frame member at the oppositeextremity fromsaid magnets, said reed at its free end being positionedbetween the ends of said permanent magnet, magnetic means mounted onsaid reed between said magnets, a coil encircling said free end of saidreed and said magnetic means and positioned within an aperture in saidframe between the extremities in said magnet members, said coil beingadapted to be energized from a source of alternating current tomagnetize said magnetic means with opposite polarities such that saidreed is attracted between the extremities of said magnets to causevibration of said reed, a pair of flexible contact carrying membersmounted on and insulated from said reed, stationary contact membersmounted on said frame member, said stationary contact members includingmounting blocks slidably positioned in a second pair of transverselyextending slots in said frame member with contacts adjustably positionedtherein, means insulating said blocks from said frame member, and meansadjustably securing said blocks to said frame member.

8. In a vibrator, a non-magnetic frame member having a longitudinallyextending slot therein, a pair of U-shaped permanent magnet memberspositioned in transversely extending slots in one end of said framemember and extending into said longitudinally extending slot with theextremities of said magnet in near abutting relationship, a flexiblereed of non-magnetic material positioned in said longitudinallyextending slot and rigidly secured to said frame member at the oppositeextremity from said magnets, said reed at its free end being positionedbetween the ends of said permanent magnets, magnetic means mounted onsaid reed between said magnets, a coil encircling said free end of saidreed and said magnetic means and positioned within an aperture in saidframe between the extremities in said magnet, said coil being adapted tobe energized from a source of alternating current to magnetize saidmagnetic means with opposite polarities such that said reed is attractedbetween the extremities of said magnets to cause vibration of said reed,a pair of flexible contact carrying members mounted on and insulatedfrom said reed, stationary contact members mounted on saidframe member,said stationary contact members including mounting blocks slidablypositioned in a second pair of transversely extending slots in saidframe member with contacts adjustably positioned therein, meansinsulating said blocks from said frame member, and means adjustablysecuring said blocks to said frame member, said last named means rigidlysecuring said contacts within said contact mounting blocks.

9. In a device of the class described, a nonmagnetic frame member havinga longitudinally extending slot therein, a pair of permanent magnetspositioned in one end of said frame member in a pair of transverselyextending slots with the extremities of said permanent magnets in' nearabutting relationship, a non-magnetic reed positioned in saidlongitudinally extending slot, means including a screw means forsecuring one extremity of said reed Within the extremity of said slotremote from said magnets such that the free extremity of said reed islocated between the free extremities of said magnets, magnetic 9 meansmounted on the free extremity of said reed between said magnets, anenergizing winding encircling said reed and said magnetic meanspositioned between said permanent magnets within said frame member, aflexible contact means mounted on said reed, stationary contact meansmounted on said frame member and including a mounting block slidablypositioned in a second transversely extending slot in said frame memher,second contact means including a contact pin adjustably positionedwithin said contact block, means insulating said contact block from saidframe member, and means adjustably securing said contact block to saidframe and said contact pin within said contact block.

10. In a device of the class described, a nonmagnetic frame memberhaving a longitudinally extending slot therein, a pair of permanentmagnets positioned in one end of said frame member in a pair oftransversely extending slots with the extremities of said permanentmagnets in near abutting relationship, a reed member positioned in saidlongitudinally extending slot, means including a screw means forsecuring one extremity of said reed within the extremity of said slotremote from said magnets such that the free extremity of said reed islocated between the free extremities of said magnets, said reed memberincluding a magnetic portion at the free extremity of said reed betweensaid magnets, an energizing winding encircling said reed positionedbetween said permanent magnets within said frame member, a flexiblecontact means mounted on said reed, stationary contact means mounted onsaid frame member and including a mounting block slidably positioned ina second transversely extending slot in said frame member, secondcontact means including a contact pin adjustably positioned Within saidcontact block, means insulating said contact block from said framemember, and means adjustably securing said contact block to said frameand said contact pin within said contact block.

THEODORE J. WILSON.

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